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Artificial insemination (AI) with liquid-preserved semen has recently become common in pig breeding. The semen doses are produced in a centralized manner at the boar stud and then subsequently distributed and transported to sow farms. However, vibration emissions during transportation by logistic vehicles may adversely affect the quality of boar sperm. Therefore, this study aimed to explore the impact of vibration-induced emissions on sperm quality and function under simulated transportation conditions. Each time, ejaculates from all 15 boars were collected and then pooled together to minimize individual variations, and the sample was split using an extender for dilution. Different rotational speeds (0 rpm, 80 rpm, 140 rpm, 200 rpm) were utilized to simulate varying intensities of vibration exposure using an orbital shaker, considering different transportation times (0 h, 3 h, and 6 h). Subsequently, evaluations were conducted regarding sperm motility, plasma membrane integrity, acrosome integrity, mitochondrial function, adenosine triphosphate (ATP) levels, mitochondrial reactive oxygen species (ROS) levels, pH, glycolytic pathway enzyme activities, and capacitation following exposure to vibration emissions. Both vibration time and intensity impact sperm motility, plasma membrane integrity, and acrosomal integrity. Vibration exposure significantly reduced sperm ATP levels, mitochondrial membrane potential, and the levels of mitochondria-encoded proteins (MT-ND1, MT-ND6) (p < 0.05). After vibration emission treatment, the pH value and mitochondrial ROS levels significantly increased (p < 0.05). Inhibition of sperm glycolysis was observed, with reduced activities of hexokinase (HK), pyruvate kinase (PK), and lactate dehydrogenase (LDH), along with decreased lactate levels (p < 0.05). Additionally, sperm tyrosine phosphorylation levels were significantly reduced by vibration emissions compared to the control group (p < 0.05). After the vibration emission treatment, the number of sperm bound to each square millimeter of oviduct explants decreased significantly compared to the control group (p < 0.05). Similarly, compared to the control group, using semen subjected to vibration stress for AI results in significantly reduced pregnancy rates, total born litter size, live-born litter size, and healthy born litter size (p < 0.05).

Abstract Terahertz (THz) technology has attracted great attention in the past few decades for its unique applications in various fields, including spectroscopy, noninvasive detection, wireless communications, and imaging. In parallel to this, the practical, fast, and broadband modulation of THz waves is becoming indispensable. Two‐dimensional (2D) materials exhibit unusual optical and electrical properties, which has prompted tremendous interest and significant advances in THz modulation. This review provides the recent progress in 2D materials‐based THz modulators, outlining the operating principles, including all‐optical, electro‐optic, magneto‐optic, and other exotic mechanisms. We focus on the recent advances in THz modulation by the designed photonic structures, such as heterostructure, metamaterial, capacitor, optical cavity, and waveguide integration. Lastly, we discussed the challenges and opportunities for 2D materials‐based THz modulators and presented our prospects for the future development.

Single crystals of the perovskite nickelate NdNiO3 with dimensions of up to 50 μm on edge have been successfully grown using the flux method at a temperature of 400 °C and oxygen pressure of 200 bar. The crystals were investigated by a combination of techniques, including high-resolution synchrotron X-ray single-crystal and powder diffraction and physical property measurements such as magnetic susceptibility and resistivity. Resistivity measurements revealed a metal-insulator transition (MIT) at TMIT~180 K with apparent thermal hysteresis; however, no superlattice peaks or peak splitting below TMIT, which corresponds to a structural transition from Pbnm to P21/n, was observed. The successful growth of NdNiO3 crystals at relatively low temperatures and oxygen pressure provides an alternative approach for preparing single crystals of interesting perovskites such as RNiO3 (R = Sm-Lu) and parent phases of superconducting square planar nickelates.

The ocean-going environment is complex and changeable with great uncertainty, which poses a huge challenge to the navigation ability of ships working in the pelagic ocean. In this paper, in an attempt to deal with the complex uncertain interference that the environment may bring to the strap-down inertial navigation system/polarization navigation system/geomagnetic navigation system (SINS/PNS/GMNS) integrated navigation system, the multi-mode switching variational Bayesian adaptive Kalman filter (MMS-VBAKF) algorithm is proposed. To be more specific, to identify the degrees of measurement interference more effectively, we design an interference evaluation and multi-mode switching mechanism using the original polarization information and geomagnetic information. Through this mechanism, the interference to the SINS/PNS/GMNS navigation system is divided into three cases. In case of slight interference (case SI), the variational Bayesian method is adopted directly to solve the problem that the statistical characteristics of measurement noise are unknown. By the fixed-point iteration mechanism, the statistical properties of the measurement noise and the system states can be estimated adaptively in real time. In case of interference-tolerance (case TI), the estimation of the statistical characteristics of measurement noise need to weigh the measurement information at the moment and a priori value information comprehensively. In case of excessive interference (case EI), the SINS/PNS/GMNS integrated navigation system will perform mode switching and filtering system reconstruction in advance. Then, the information fusion and navigation states estimation can be completed. Consequently, the reliability, robustness, and accuracy of the SINS/PNS/GMNS integrated navigation system can be guaranteed. Finally, the effectiveness of the algorithm is illustrated by the simulation experiments.

In this paper, to address the problem of positioning accumulative errors of the inertial navigation system (INS), a bionic autonomous positioning mechanism integrating INS with a bioinspired polarization compass is proposed. In addition, the bioinspired positioning system hardware and the integration model are also presented. Concerned with the technical issue of the accuracy and environmental adaptability of the integrated positioning system, the sun elevation calculating method based on the degree of polarization (DoP) and direction of polarization (E-vector) is presented. Moreover, to compensate for the latitude and longitude errors of INS, the bioinspired positioning system model combining the polarization compass and INS is established. Finally, the positioning performance of the proposed bioinspired positioning system model was validated via outdoor experiments. The results indicate that the proposed system can compensate for the position errors of INS with satisfactory performance.

Two-dimensional (2D) materials driven by their unique electronic and optoelectronic properties have opened up possibilities for their various applications. The large and high-quality single crystals are essential to fabricate high-performance 2D devices for practical applications. Herein, IV-V 2D GeP single crystals with high-quality and large size of 20 × 15 × 5 mm3 were successfully grown by the Bi flux growth method. The crystalline quality of GeP was confirmed by high-resolution X-ray diffraction (HRXRD), Laue diffraction, electron probe microanalysis (EPMA) and Raman spectroscopy. Additionally, intrinsic anisotropic optical properties were investigated by angle-resolved polarized Raman spectroscopy (ARPRS) and transmission spectra in detail. Furthermore, we fabricated high-performance photodetectors based on GeP, presenting a relatively large photocurrent over 3 mA. More generally, our results will significantly contribute the GeP crystal to the wide optoelectronic applications.

Investigating celestial polarization patterns in the case of different environments is important for exploring the atmospheric radiative transfer mechanism. Although intensive studies on clear sky, foggy sky, and even total solar eclipse sky have been conducted, the polarization distribution generated by the moonlight has not been well investigated. This study analyzes celestial polarization patterns generated by the Super Blue Blood Moon (SBBM) through several comparative studies. The polarization patterns under the SBBM are collected, analyzed, and compared with both those generated by the ideal single-scattering Rayleigh model and those in the normal sky. From the analysis of the relative variation of the celestial polarization characteristics including the Degree of Polarization (DoP) and Angle of Polarization (AoP), the changes of the extremum, frequency, symmetric line, and neutral points are discussed. As a result, SBBM polarization patterns change at the beginning of the partial eclipse, and the neutral points vary from traditional neutral points. The value of DoP gradually decreases as the obscuration ratio of the Moon increases. The AoP is no longer symmetrical about the celestial meridian. As a conclusion, it is suggested that the variation of the polarized skylight during the SBBM should be considered in atmospheric model calculation for nocturnal biological activity and navigation information computation.

TiO2/carbon fiber composite is achieved by loading TiO2 nanoparticles on biomass carbon fiber, which originates from the carbonized natural bast. The carbonized process and the loading amount of TiO2 are researched in detail. It is found that the carbonized bast fiber shows robust adsorption characteristics for TiO2 nanoparticles in aqueous dispersion, and TiO2 nanoparticles with ~15 wt.% in total weight are uniformly loaded onto the fiber surface. The photocatalytic properties of TiO2/carbon fiber composite are evaluated by photocatalytic degradation of rhodamine B and water splitting for hydrogen production. The results indicate that 90% RhB molecules could be attacked in 60 min under UV light irradiation, and the hydrogen production rate of water splitting is up to 338.51 μmol/h. The highlight is that TiO2/carbon fiber composite is easy to be recycled due to the incorporation of macroscopical biomass carbon fiber.

The electro-optic (EO) property of hexagonal Cs2TeMo3O12 (CTM) crystal is studied with interference technique at 632.8 nm. Both the value and sign of the EO coefficients have been obtained and confirmed. The largest EO coefficient is 10.4 pm/V for r33 due to its structure distortion along c-axis. The transverse effective EO effect of r33 and the half-wave voltage are calculated to be 11.08 pm/V and 5200V at 1064 nm, respectively. The experimental results show that CTM can be one of promising candidates for the EO applications, especially in the mid-infrared region. [ABSTRACT FROM AUTHOR]

The refractive indices of 4H- and 6H-SiC single crystals at wavelengths of 404.7, 435.8, 480.0, 546.1, 587.5, 643.8, 706.5, 852.1, 1014.0, 1529.6, and 2325.4 nm are carefully measured from 293 to 493K by the method of minimum deviation. We find that ordinary (no) and extraordinary (ne) refractive indices for both crystals increase with the elevated temperature. The temperature-dependent Sellmeier equations of refractive indices for 4H- and 6H-SiC are obtained and then thermo-optic coefficients (TOCs) are derived. The TOCs diminish very quickly at visible light region and become less dependent in the infrared light region. Such changing trends of TOCs can be explained by singleoscillator approximation. The results may provide the important reference value for designing the optoelectronic and nonlinear optical devices based on SiC. [ABSTRACT FROM AUTHOR]

Direct deposition of isolated metal atoms onto substrates has been recognized as a simple route to obtain high performance supported atomically dispersed metals (SACs), however, the agglomeration driven by high surface energy is difficult to avoid. Herein, we demonstrate a one-pot solution synthesis to obtain atomically dispersed platinum(Pt) supported on nitrogen (N)-dopedmesoporous carbon (NMC) substrates (Pt/NMC-LT) by conducting the whole synthesis at -40 °C, owing to the sluggish nucleation kinetics. We obtained the Pt/NMC-LT catalyst with superior electrochemical hydrogen evolution reaction (HER) activity and stability, in comparison with the NMC supported dominant Pt sub-nanometer cluster catalyst from solution synthesis at RT ~ 25 °C (Pt/NMC-RT) and commercial carbon supported Pt nanoparticle catalysts (Pt/C). Lower overpotential values (only 17.0 and 49.8 mV) are needed for high HER current densities (10 and 100 mA cm-2, respectively), and no obvious degradation is observed after an accelerated durability test (ADT) for 5000 CV cycles. [ABSTRACT FROM AUTHOR]

Single crystals of an environmental friendly material LiInSe2 (LISe) with dimensions up to Φ16 mm × 55 mm were grown successfully through a modified vertical Bridgman technique. The quality of the crystal was measured by a high resolution X-ray diffraction rocking curve, and a full width at half-maximum (fwhm) for a, b, and c faces are 47", 46", 36", respectively. It indicates that the as-grown crystal is high quality. The complete sets of dielectric, elastic, and piezoelectric constants of LISe crystals at room temperature were obtained by the resonant technique and impedance analysis for the first time. The piezoelectric constants d24 and d33 reached -13.6 pC/N and 8.5 pC/N, respectively. The corresponding electromechanical coupling coefficient k33 is 21%. In addition, the structural distortions and dipole moments of LISe were analyzed in detail. Our results show that LISe is a promising candidate as an environmental friendly piezoelectric material. [ABSTRACT FROM AUTHOR]

Three calcium silicon phosphides: Ca2Si2P4, Ca3Si8P14, and Ca3Si2P4 were synthesized by solid state reaction and identified by single-crystal X-ray diffraction. Ca2Si2P4 crystallizes in the noncentrosymmetric space group P41212 (no.92) with a = 7.173 Å, c = 26.295 Å. Both Ca3Si8P14 and Ca3Si2P4 crystallize in the space group P21/ c (no.14) with a = 12.138 Å, b = 13.476 Å, c = 6.2176 Å, β = 90.934°, and a = 7.073 Å, b = 17.210 Å, c = 6.918 Å, β = 111.791°, respectively. The Si-P tetrahedra construct one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) networks in Ca3Si2P4, Ca2Si2P4, and Ca3Si8P14, respectively, and their calculated bandgaps are 0.826, 0.984, and 0.829 eV, respectively. [ABSTRACT FROM AUTHOR]

Singlecrystal LiInS2(LIS) is a promising candidate for mid-infrared(MIR) frequency conversion to obtain MIR laser output. Large-sizedLIS crystals with a diameter of 16 mm and a length of 50 mm were grownby the modified Bridgman method. The as-grown LIS crystals were annealedin different atmospheres, and the effects of annealing on the electricaland optical properties were studied in detail. The visible-near-infraredand MIR transmission spectra of the crystals were studied before andafter annealing in different atmospheres. The experimental resultsindicate that the optimal annealing conditions for a grown crystalare to use an atmosphere of LIS vapor at 700 °C for 160 h. Theelectrical properties were investigated before and after annealingin the LIS vapor atmosphere. After proper postgrowth annealing, thequality of the crystal was significantly improved, which resultedin an increase in the damage threshold from 0.9 to 1.2 J/cm2. [ABSTRACT FROM AUTHOR]

A mid-infrared LiInSe2 (LISe) single crystal was successfully grown by the modified vertical Bridgman technique with dimensions of about Ø12 mmx30 mm. A large amount of high purity polycrystalline LISe used for crystal growth was synthesized in one run by a novel two-step synthesis method. The thermal properties of the crystal were carefully investigated by measuring the melting point, specific heat, and thermal diffusivity, and deriving the thermal conductivity. The transmission spectrum showed that the 50% transmittance level extends from 0.65 to 12.6 µm. The excellent thermal conductivity and optical properties indicate that LISe is one of only a few promising candidates for high average power nanosecond OPOs pumped by ~1 µm lasers. [ABSTRACT FROM AUTHOR]

The electro-optic (EO) properties of monoclinic BaTeMo2O9 (BTM) single crystals are studied using the interference technique by applying the external electric field. The measured room temperature free EO coefficients at 632.8 nm are 10.2 and 9.0 pm/V for γ12 and γ41, respectively. The EO effect (-12ni3γijE) of BTM is about three times as high as that of KH2PO4 (KDP) crystal, which makes it a very promising candidate for the EO applications. [ABSTRACT FROM AUTHOR]

We investigate free carriers dynamics and anharmonic decay of optical phonons in LiInSe2 by using low temperature THz time-domain spectroscopy. The quantitatively determined refractive index and absorption coefficient are significantly influenced by temperature. By fitting the evaluated dielectric functions with a Drude-Lorentz model, the temperature dependencies of the plasmon frequency, scattering rates of free carriers, activation energies of carriers, and frequencies and linewidths of optical phonons are investigated. The contributions of three- and four-phonon processes to the temperature dependent optical phonon frequency and linewidth variations are quantitatively determined. [ABSTRACT FROM AUTHOR]

Three calcium silicon phosphides: Ca2Si2P4, Ca3Si8P14, and Ca3Si2P4 were synthesized by solid state reaction and identified by single-crystal X-ray diffraction. Ca2Si2P4 crystallizes in the noncentrosymmetric space group P41212 (no.92) with a = 7.173 Å, c = 26.295 Å. Both Ca3Si8P14 and Ca3Si2P4 crystallize in the space group P21/ c (no.14) with a = 12.138 Å, b = 13.476 Å, c = 6.2176 Å, β = 90.934°, and a = 7.073 Å, b = 17.210 Å, c = 6.918 Å, β = 111.791°, respectively. The Si-P tetrahedra construct one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) networks in Ca3Si2P4, Ca2Si2P4, and Ca3Si8P14, respectively, and their calculated bandgaps are 0.826, 0.984, and 0.829 eV, respectively. [ABSTRACT FROM AUTHOR]